Continuous process for manufacturing superabsorbent polymer
US6187828A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 24, 1998 |
| Grant date | Feb 13, 2001 |
| Priority date | — |
| Expiry date | Nov 24, 2018 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61F2013/530489
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
Disclosed herein is a continuous process to make super absorbing polymer characterized by feeding at the head-end of a pressurized vessel, an aqueous solution of SAP forming monomer solution, either in un-neutralized or pre-neutralized condition, the monomer(s) being conveyed to the reactor vessel at a relatively low temperature of from 5.degree. C. to 15.degree. C. into a pressurized head feed zone of the reactor. The head pressure is maintained the reactor at a minimum level of greater than or equal to about 20 p.s.i.g. and the SAP advances to the discharge end. A relatively constant mass of SAP is maintained of at least 50% volume of SAP in the vessel, and the rate of entry and exit are kept relatively constant. The reaction vessel is equipped with a venting means to regulate the internal bead pressure to advance the SAP to the discharge end without mechanical agitation. The continuous polymerization process is followed by drying and pulverizing the discharged SAP polymer, including optional post-treatment steps.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.